Question

Explain the differences among hierarchical, network, and relational data models. What makes the relational data model the most popular data model in use today? (DQ 4-1)

Answer 1

The world of data is constantly changing and evolving every second.This in turn has created a completely new dimension of growth and challenges for companies around the globe.By accurately recording data, updating and tracking them on an efficient and regular basis,companies can address their challenges on one hand and make use of the immense potential offered by this sector on the other hand.

By collecting minute and updated data,companies are using the said information to achieve their goals in a systematic way on one hand and empower their business in a strategic manner on the activities conducted after collection of data includes creating accounting reports,calculating sales estimates and creating invoices of customers.This data and it's insights is then made available to the management and employees of the organization through computerized database.One of the proven ways in which brands can manage the relationships between the various database elements is through the use of database management systems,which is today an integral part of functioning of companies and organizations around the world.

Database management system are therefore crucial and important links in the creation as well as management of data .They are needed for effective running and management of data.it also helps companies to transfer the said data through the entire systems.Some of the major types of database that exist in the industry today includes the following

Hierarchical database model

A hierarchical database model is a data model in which the data are organized into a tree-like structure.The data are stored as records which are connected to one another through links.A record is a collection of fields,with each field containing only one value.The type of a record defines which fields the record contains.

The hierarchical database model mandates that each child record has only one parent,whereas each parent record can have one or more child records.In order to retrieve data from a hierarchical database the whole tree needs to be traversed starting from the root node.This model is recognized as the first database model created by IBM in the 1960s.

Network Database management systems

A network model is a database model that is designed as a flexible approach to representing objects and their relationships.A uniqur feature of the network model is it's schema,which is viewed as a graph where relationship types are arcs and object types are nodes.Unlike other database models,the network model's schema is not confined to be a lattice or hierarchy;the hierarchical tree is replaced by a graph,which allows for more basic connections with the nodes.

Relational Database management system

The relational model(RM) for database management is an approach to managing data using a structure and language consistent with first-ordet predicate logic,first described in 1969by English computer scientist Edgar F.Codd,where all data is represented in terms of tuples,grouped into relations.A database organized in terms of relational model is a relational database.

The purpose of the relational model is to provide a declarative method for specifying data and queries:users directly state what information the database contains and what information the want from it,and let the database management system software take care of describing data structures for storing the data retrieval procedures for answering queries.

Most relational databases use the SQL data definition and query language;these systems implement what can be regarded as an engineering approximation to the relational model.A table in an SQL database schema corresponds to a predicate variable; the contents of a table to a relation;key constraints,other constraints,and SQL queries correspond to predicates.However,SQL databases deviates from the relational model in many details,and Codd fiercely argued against deviations that compromise the original principles.

A relational database is a database that presents all data to its clients as relations as defined in the relational model.Being even simpler than the other answers,a relational database keeps everything in tables,with rows.All the rows in the table have the same kinds of data in the columns.

A major hurdle is choosing the right database management system so that brands can achieve their goals,both short and long term in a systematic fashion.By combining your requirements and understanding various data sources as well as handling updates on your system in proper manner,brands can very easily choose the right database management system for their brands.